England coach Stuart Lancaster refused to question his players' decision-making after some costly calls in a narrow 20-14 defeat to Australia at Twickenham.

Lancaster saw his side twice turn down kickable penalties in favour of a tap and go or a lineout in a close encounter with the Wallabies and those gambles failed to pay off with the vsitors claiming a narrow 20-14 victory and with it the Cook Cup.

Lancaster said: "I'm disappointed we lost but I thought Australia played a smart game and bounced back from their defeat against France last week and were competitive in all areas.

"There were lots of positives from our own performance but the reality is we needed to take the opportunities we created, especially in the last 20 minutes when we thought our tempo would pay. They are the lessons we have to learn for South Africa next week.

"We'll look at every decision but with the momentum at the time I thought it was the right decision. You back your players on the field. The momentum was with us and I thought from there we were going to score a try. If we are going to give players the confidence to go out and play then we have to back them.

"We have areas to work on, but there was lots of intent to play. It was just little bits of execution towards the end of each phase that put us under pressure."

Lancaster, however, was upbeat, believing his players can turn things around against South Africa next weekend with the All Blacks set to follow them to Twickenham the week after. "They are all must-win games," he admitted. "We're devastated to have lost this game. We didn't quite take our opportunities and at this level we must take it. They managed the breakdown better."

Asked if seven days was enough time to put things right, Lancaster added: "Of course it is. Every game's a new game. You learn, review and move on. "We have got to be better. Australia proved in their 18-18 draw with New Zealand they can put out a performance at the top end and they have done that today. We'll look at the tape and talk it through, train and learn our lessons."

England defence coach Andy Farrell was also impressed with the Australian performance.

He said: "Australia played a very smart game. Their attack was good and asked a lot of questions. We weathered the storm but theirs was a messy breakdown and penalties and it was stop-start. But all round you have to take your hat off to Australia. They didn't look desperate, they looked controlled."